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Detecting gastrointestinal (GI) infection transmission among men who have sex with men (MSM) in England is complicated by a lack of routine sexual behavioural data. We investigated whether gender distributions might generate signals for increased transmission of GI pathogens among MSM. We examined the percentage male of laboratory-confirmed patient-episodes for patients with no known travel history for 10 GI infections of public health interest in England between 2003 and 2013, stratified by age and region. An adult male excess was observed for Shigella spp. (annual maximum 71% male); most pronounced for those aged 25–49 years and living in London, Brighton and Manchester. An adult male excess was observed every year for Entamoeba histolytica (range 59.8–76.1% male), Giardia (53.1–57.6%) and Campylobacter (52.1–53.5%) and for a minority of years for hepatitis A (max. 69.8%) and typhoidal salmonella (max. 65.7%). This approach generated a signal for excess male episodes for six GI pathogens, including a characterised outbreak of Shigella among MSM. Stratified analyses by geography and age group were consistent with MSM transmission for Shigella. Optimisation and routine application of this technique by public health authorities elsewhere might help identify potential GI infection outbreaks due to sexual transmission among MSM, for further investigation.
Complications from systemic inflammation are reported in neonates following exposure to cardiopulmonary bypass. Although the use of asanguinous primes can reduce these complications, in neonates, this can result in significant haemodilution, requiring addition of blood. This study investigates whether the addition of blood after institution of bypass alters the inflammatory response compared with a blood prime. Neonatal swine were randomised into four groups: blood prime, blood after bypass but before cooling, blood after cooling but before low flow, and blood after re-warming. All groups were placed on central bypass, cooled, underwent low flow, and then re-warmed for a total bypass time of 2 hours. Although haematocrit values between groups varied throughout bypass, all groups ended with a similar value. Although they spent time with a lower haematocrit, asanguinous prime groups did not have elevated lactate levels at the end of bypass compared with blood prime. Asanguinous primes released less tumour necrosis factor α than blood primes (p=0.023). Asanguinous primes with blood added on bypass produced less interleukin 10 and tumour necrosis factor α (p=0.006, 0.019). Animals receiving blood while cool also showed less interleukin 10 and tumour necrosis factor α production than those that received blood warm (p=0.026, 0.033). Asanguinous primes exhibited less oedema than blood primes, with the least body weight gain noted in the end cool group (p=0.011). This study suggests that using an asanguinous prime for neonates being cooled to deep hypothermia is practical, and the later addition of blood reduces inflammation.
We have investigated the physical properties of molecular clouds which are presumably interacting with the G359.54+0.18 Nonthermal Filaments and an associated H ii region east of the filaments (Staguhn et al., 1996). The sub-mm spectra of 12CO(3-2) were observed with the KOSMA 3 m telescope, while the 490 GHz [C i] 3P1 →3P0 observations were made with the AST/RO 1.7 m sub-mm telescope. Fig. 1 shows channel maps of the integrated CO and [C i] line intensities in the velocity range of the recombination line observed towards the nearby H ii region. This H ii region is traced by the VLA 5 GHz continuum observations which are shown as contours in the central parts of the maps. The G359.54+0.18 Nonthermal Filaments, situated further to the west, appear to be morphologically associated with the H ii region. The [C i] emission of the molecular cloud east of the filaments which is kinematically linked to the H ii region is anti-correlated with the molecular line emission over a large angular extent. It is unlikely that the large morphological differences between [C i] and CO in this region can be explained exclusively by a high abundance of neutral carbon in the surface regions of dense molecular clumps, as is usually the case in PDR regions near the Sun.
Item response theory (IRT) analyses of alcohol use disorder (AUD) and other psychological disorders are a predominant method for assessing overall and individual criterion severity for psychiatric diagnosis. However, no investigation has established the consistency of the relative criteria severities across different samples.
PubMed/Medline, PsycINFO, Web of Science and ProQuest databases were queried for entries relating to alcohol use and IRT. Study data were extracted using a standardized data entry sheet. Consistency of reported criteria severities across studies was analysed using generalizability theory to estimate generalized intraclass correlations (ICCs).
A total of 451 citations were screened and 34 papers (30 unique samples) included in the research synthesis. The AUD criteria set exhibited low consistency in the ordering of criteria using both traditional [ICC = 0.16, 95% confidence interval (CI) 0.06–0.56] and generalized (ICC = 0.18, 95% CI 0.15–0.21) approaches. These results were partially accounted for by previously studied factors such as age and type of sample (e.g. clinical v. community), but the largest source of unreliability was the diagnostic instrument employed.
Despite the robust finding of unidimensional structure of AUDs, inconsistency in the relative severities across studies suggests low replicability, challenging the generalizability of findings from any given study. Explicit modeling of well-studied factors like age and sample type is essential and increases the generalizability of findings. Moreover, while the development of structured diagnostic interviews is considered a landmark contribution toward improving psychiatric research, variability across instruments has not been fully appreciated and is substantial.
Our previous observations established the small angular size and high brightness temperature of emission from the v=1, J=1-0 transition of SiO from the circumstellar envelopes of the supergiant VX Sgr and the Mira variable R Cas. We performed a second VLBI experiment on the SiO masers in several late type stars on 31 Oct.-2 Nov. 1978 to compare the physical characteristics of the SiO masers in the v=1 and v=2 states. With an energy separation of 1258 cm-1 (an equivalent temperature of 1753 K) between the two vibrational states, differences in excitation and pumping of the maser states may lead to different maser properties.
A symptom of mild cognitive impairment (MCI) and Alzheimer’s disease
(AD) is a flat learning profile. Learning slope calculation methods vary, and
the optimal method for capturing neuroanatomical changes associated with MCI and
early AD pathology is unclear. This study cross-sectionally compared four
different learning slope measures from the Rey Auditory Verbal Learning Test
(simple slope, regression-based slope, two-slope method, peak slope) to
structural neuroimaging markers of early AD neurodegeneration (hippocampal
volume, cortical thickness in parahippocampal gyrus, precuneus, and lateral
prefrontal cortex) across the cognitive aging spectrum [normal
control (NC); (n=198;
age=76±5), MCI (n=370;
age=75±7), and AD (n=171;
age=76±7)] in ADNI. Within diagnostic group,
general linear models related slope methods individually to neuroimaging
variables, adjusting for age, sex, education, and APOE4 status. Among MCI,
better learning performance on simple slope, regression-based slope, and late
slope (Trial 2–5) from the two-slope method related to larger
parahippocampal thickness (all p-values<.01) and
hippocampal volume (p<.01). Better regression-based
slope (p<.01) and late slope
(p<.01) were related to larger ventrolateral
prefrontal cortex in MCI. No significant associations emerged between any slope
and neuroimaging variables for NC (p-values ≥.05) or
AD (p-values ≥.02). Better learning performances
related to larger medial temporal lobe (i.e., hippocampal volume,
parahippocampal gyrus thickness) and ventrolateral prefrontal cortex in MCI
only. Regression-based and late slope were most highly correlated with
neuroimaging markers and explained more variance above and beyond other common
memory indices, such as total learning. Simple slope may offer an acceptable
alternative given its ease of calculation. (JINS, 2015,
The association between depression after myocardial infarction and increased risk of mortality and cardiac morbidity may be due to cardiac disease severity.
To combine original data from studies on the association between post-infarction depression and prognosis into one database, and to investigate to what extent such depression predicts prognosis independently of disease severity.
An individual patient data meta-analysis of studies was conducted using multilevel, multivariable Cox regression analyses.
Sixteen studies participated, creating a database of 10 175 post-infarction cases. Hazard ratios for post-infarction depression were 1.32 (95% CI 1.26–1.38, P<0.001) for all-cause mortality and 1.19 (95% CI 1.14–1.24, P<0.001) for cardiovascular events. Hazard ratios adjusted for disease severity were attenuated by 28% and 25% respectively.
The association between depression following myocardial infarction and prognosis is attenuated after adjustment for cardiac disease severity. Still, depression remains independently associated with prognosis, with a 22% increased risk of all-cause mortality and a 13% increased risk of cardiovascular events per standard deviation in depression z-score.
Exposure to intrauterine growth restriction (IUGR) is an important risk factor for impaired learning and memory, particularly in males. Although the basis of IUGR-associated learning and memory dysfunction is unknown, potential molecular participants may be insulin-like growth factor 1 (Igf1) and its receptor, IGF1r. We hypothesized that transcript levels and protein abundance of Igf1 and IGF1r in the hippocampus, a brain region critical for learning and memory, would be lower in IUGR male rats than in age-matched male controls at birth (postnatal day 0, P0), at weaning (P21) and adulthood (P120). We also hypothesized that changes in messenger Ribonucleic acid (mRNA) transcript levels and protein abundance would be associated with specific histone marks in IUGR male rats. Lastly, we hypothesized that IUGR male rats would perform poorer on tests of hippocampal function at P120. IUGR was induced by bilateral ligation of the uterine arteries in pregnant dams at embryonic day 19 (term is 21 days). Hippocampal Igf1 mRNA transcript levels and protein abundance were unchanged in IUGR male rats at P0, P21 or P120. At P0 and P120, IGF1r expression was increased in IUGR male rats. At P21, IGF1r expression was decreased in IUGR male rats. Increased IGF1r expression was associated with more histone 3 lysine 4 dimethylation (H3K4Me2) in the promoter region. In addition, IUGR male rats performed poorer on intermediate-term spatial working memory testing at P120. We speculate that altered IGF1r expression in the hippocampus of IUGR male rats may play a role in learning and memory dysfunction later in life.
L’utilisation du tritium dans les réacteurs CANDU (Canada Deutérium Uranium), dans
l’industrie, pour la production de sources et de peintures luminescentes, dans
l’exploration pétrolière et gazière, dans les hôpitaux pour des tests diagnostiques, en
radiothérapie et en recherche, rend le contrôle de ses rejets particulièrement important
au Canada. Ces rejets sont réglementés et étroitement surveillés par la Commission
canadienne de sûreté nucléaire (CCSN). Certains groupes d’intérêt et de citoyens
prétendent cependant que l’incertitude scientifique sur les effets du tritium sur la santé
et l’environnement est telle que la réglementation des installations rejetant ou utilisant
du tritium serait inadéquate. Pour répondre à ces inquiétudes, la CCSN a demandé à son
personnel d’entreprendre le projet intitulé « Études sur le tritium ».
Dans le cadre de ce projet, le devenir du tritium dans l’environnement ainsi que ses
effets sanitaires, ont été étudiés au moyen de mesures directes sur le terrain ainsi qu’à
travers la revue de la littérature scientifique la plus récente sur le sujet. Ce projet a
permis de conclure que les mesures de radioprotection concernant le tritium ainsi que les
mécanismes utilisés pour le réglementer sont adéquats pour protéger la santé et la
sécurité des Canadiens.
FS Aurigae is famous for a variety of uncommon and puzzling periodic photometric and spectroscopic variabilities which do not fit well into any of the established sub-classes of cataclysmic variables. Here we present preliminary results of long-term monitoring of the system, conducted during the 2010-2011 observational season. We show that the long-term variability of FS Aur and the character of its outburst activity may be caused by variations in the mass transfer rate from the secondary star as the result of eccentricity modulation of a close binary orbit induced by the presence of a third body on a circumbinary orbit.
Climate change during the so-called Little Ice Age (LIA) of the 15th to 19th centuries was once thought to be limited to the high northern latitudes, but increasing evidence reflects significant climate change in the tropics. One of the hypothesized features of LIA climate in the low latitudes is a more southerly mean annual position of the Intertropical Convergence Zone (ITCZ), which produced more arid conditions through much of the northern tropics. High-resolution stable oxygen isotope data and other sedimentary evidence from Laguna de Felipe, located on the Caribbean slope of the Cordillera Central of the Dominican Republic, support the hypothesis that the mean annual position of the ITCZ was displaced significantly southward during much of the LIA. Placed within the context of regional paleoclimate and paleoceanographic records, and reconstructions of global LIA climate, this shift in mean annual ITCZ position appears to have been induced by lower solar insolation and internal dynamical responses of the global climate system. Our results from Hispaniola further emphasize the global nature of LIA climate change and the sensitivity of circum-Caribbean climate conditions to what are hypothesized to be relatively small variations in global energy budgets.
Microcrystalline inclusions in hydrogenated and fluorinated amorphous silicongermanium alloys, α-Si, Ge:H, F, were studied. Microcrystals grown during RF or DC glow discharge deposition from SiF4, GeF4 and H2 consist of either pure Si or Ge. Microcrystals produced by thermal annealing of initially amorphous alloys are either microcrystalline Ge or microcrystalline Si-Ge alloys depending on the annealing temperature. Values for the grain size were calculated from X-ray diffraction (XRD) and Raman spectra. The grain size of the “grown” microcrystal ranges from 8 to 60 nm. These grown grains exhibit preferential orientation of the (220) planes parallel to the substrate surface. Microcrystals produced by high-temperature anneal are randomly oriented. Scanning electron micrographs of as-grown samples show protruding platelets several 100 nm long and several 10 nm wide. Fractured cross sections exhibit columnar structure.
Tungsten (W) films were deposited onto InP in a cold wall, rapid thermal low-pressure chemical vapor deposition (RT-LPCVD) reactor, from a tungsten hexafluoride (WF6) gas reduced by hydrogran (H2). W films of thickness 50 to 450 nm were deposited in the temperature range of 350° to 550°C, pressure range of 0.5 to 4.5 Torr and deposition rates up to 4 nm/sec with an apparent activation energy of about 1.12 eV. The film stress varied depending upon the deposition pressure, from low compressive for deposition at 0.5 Torr to moderate tensile for deposition at about 4.5 Torr. The films were aged at temperatures as high as 300°C for about 800 hr and exhibited an excellent mechanical stability. Post-deposition sintering of the W films at temperatures up to 600°C led to reduction of the resistivity with a minimum value of about 55μΩ-crn as a result of heating at 500°C. Conditions for both selective and blanket deposition were defined, and a dry etching process for further geometrical definitions of the films was developed, providing etch rates of 40 to 50 nm·sec-1. This report reflects the first attempt to deposit W films onto III-V semiconductor at a very high rate by means of RT-LPCVD.
The photoluminescence (PL), X-band ODMR. and LESR of C60 films and C60 isolated in a toluene/polystyrene glass matrix (C60:T/PS) is described. The delocalized triplet LESR and ODMR of C60:T/PS are similar to previously reported LESR. In films, however, the ODMR indicates that the delocalized triplet is larger and distorted by neighboring molecules. In addition, another, localized triplet, and a narrow PL-enhancing line at g = 2.0017 ± 0.0005 are observed. These features are similar to those observed in several π-conjugated polymers. The former is attributed to a localized triplet of size similar to a 5- or 6-membered ring, tentatively on a face adjacent to another C60 molecule; the latter is believed to result from intermolecular polaron recombination.
Some metallization systems consisting of barrier metals and Au-Sn (multiple alternating layers) were studied as a bonding schemes of InP-based laser diodes to the first time used, CVD-diamond submounts. The first system to be studied, which was traditionally used in various other applications was Ti(100nm)/Pt(200nm)/Au(500nm)/Au-Sn(2.5 μm). This structure provided a molten Au-Sn layer of eutectic composition (80:20 wt%) on top of the Ti/Pt metals for about 6 sec, while heated at temperatures of 300 to 350°C, and allowed for efficient bonding of the device to the submount. Longer heating durations, however, led to reaction between Pt and Sn to consume significant amounts of Sn from the solder, thus elevating its melting temperature and resolidifying the solder. With optimum bonding conditions, a high quality bond of the InP-based laser diode to the CVD-diamond submount was observed, and a superior electrical performance of the diode was measured compared to diodes that were bonded with the standard In/BeO configurations. In order to maintain the superior performance of the InP laser diode bonded assembly but improve the thermodynamic stability of the metallurgical system and thus extending the bonding processing window, various metals such as W and Cr were studied as a replacement for the Ti/Pt barrier metals in between the CVD-diamond submount and the Au-Sn solder. While applying the W layer, a thin Ti(10nm) layer was introduced in between it and the Au-Sn to improve the solder wettability. The W layer was found to remain intact after heating at 350°C for durations as long as 5 min, and thus, due to the inert nature of the Au-Sn/W interface, the Au-Sn ratio was kept uniform at the eutectic liquid composition through a long heating duration (up to 5 min). Minimum reaction was observed, as well, at the Au-Sn/Cr interface, while executing a Ti(100nm)/Cr(200nm)/Au-Sn(1.5 μm) system, and thus allowed for an excellent bonding of the InP laser diodes to the CVD-diamond submounts.
The photoluminescence (PL) and X-band ODMR of porous Si layers is described and discussed. The layers were prepared by anodizing the (100) face of a Si wafer at 20 mA/cm2 in 20% HF for 5 mai and passively soaking them in 36% HF for up to 10 hrs. The PL was broad and featureless, extending from ˜1.5 to ˜2.1 eV and peaking at 1.68 eV. Its intensity slightly increased upon cooling to 90 K, and then strongly decreased at lower temperatures. A ˜20 G wide asymmetric PL-enhancing ODMR was observed at g ˜2.0031 ±I 0.0009, which could be fit to a sum of two Gaussians. Their g-values were slightly temperature dependent. The ODMR intensity strongly decreased with increasing temperature, and was unobservable above ˜80 K. The results are compared to the optical properties of hydrogenated amorphous Si.
Ta2O5 and Nb2O5 films were deposited using the Lam Research Integrity™ reactor. The chemical precursors used were pentaethoxides of Ta and Nb. Typical films were deposited at a rate of 4 nm/min with uniformities of <1.5% lσ in the presence of O2 at 470°C. Annealing the Ta2O5 films did not change the O/Ta ratio. Annealing the Nb2O5 films increased the O/Nb ratio to 2.5/1 at 850°C. Interfacial SiO2 grew to 4 nm after annealing at 850°C for both Ta2O5 and Nb2O5. The as-deposited films were amorphous, but became crystalline above 600°C and 700°C for the Nb2O5 and Ta2O5 films respectively. The TEM observations on crystallization is supported by x-ray diffraction data.
Very few porous low-k dielectric materials meet the basic requirements for integration into the back end of the line (BEOL) metallization. According to the International Technology Roadmap for Semiconductors, 2005, candidates for the 45 nm node need a k<2.2 and a minimum adhesion strength of 5 J/m2. Recently, a low-k dielectric material was developed, called nano-clustered silica (NCS). It is a spin-on glass with k<2.3. NCS is constitutively porous, with a micro- and mesopore size of ~2.8 nm. The first reported adhesion strength of this material was 10+ J/m2. We investigated the nature of the adhesive strength of NCS by critical and sub-critical fracture and Fourier Transform IR Spectroscopy (FTIR). The four-point bend technique and a mixed-mode double cantilever beam technique were employed. The sub-critical crack growth studies were performed in humid environments and ambient temperatures. Different post-treatments were used on NCS to achieve different molecular structure, as measured with FTIR. A correlation between molecular structure and critical adhesion energy was found. Atomistic parameters were calculated from the sub-critical crack growth data. A dependency of fracture behavior on post-treatment and, therefore, structure was observed.